VANCOUVER -- All B.C. students in Grades 4 to 12 will now be required to wear masks in school.

Dr. Bonnie Henry announced the change in guidance during a news conference on Monday.

"We are now going to be updating our K to 12 public health guidance to support mask wearing for all students down to Grade 4 in schools across the province," Henry said, adding that officials are better understanding the "disruption" exposure events can cause in schools.

Although Dr. Henry did not explicitly say that masks would be mandatory during the news conference, CTV News Vancouver later confirmed with the B.C. Ministry of Health that masks will be required for students in Grades 4 and up.

Students in Kindergarten up to Grade 3 will not be required to wear masks, however the province recommends they do.

Miranda Tracy, a mother of two elementary school-aged boys in Aldergrove, said she welcomes the updated mask mandate, but would like to see it extend down to Kindergarten.

"Around the world there are kids that age who can wear masks no problem. Kids are very adaptable,” she says.

The union representing B.C. teachers is pleased with the expanded mask requirements.

"We welcome the additional support of the mask mandate. We also recognize that there are other measures that need to be put in place as well." says Teri Mooring, president of the B.C. Teachers' Federation.

Mooring says masks alone are not enough to stop the spread of COVID-19 in the classroom. She says many schools across the province need to implement stronger physical distancing measures, and upgrade their ventilation systems.

The update came after Surrey announced its own mandate Saturday, requiring staff teaching kindergarten to Grade 12 and students in Grades 4 to 12 classrooms to wear masks at all times, even when they're with their learning groups. 

Previously, masks were required only for students in middle and high schools, and did not have to be worn when students were sitting at their desks.

"We think this step is long overdue, but it's very welcome," Matt Westphal, president of the Surrey Teachers' Association, told CTV News in reaction to the announcement.

"We've been calling since the beginning of the year for a requirement for masks in Surrey schools because they're so crowded and it's not possible to distance."

The teachers' association says it believes younger students should be required to wear masks. Face coverings for students in kindergarten to Grade 3 are encouraged, but not mandatory.

"It's good to see a mask mandate in Surrey schools at long last," Teri Mooring, president of the B.C. Teachers' Federation, said on social media over the weekend.

"It is my hope that families will heed the strong encouragement for children in (kindergarten to Grade 3) to also wear masks. This is a good step."

Surrey has consistently been a hotspot for COVID-19 transmission in B.C., and Surrey schools have seen a significant number of coronavirus exposures, clusters and outbreaks during the current school year.

Because of this, the district has also been a priority location for teacher vaccinations under B.C.'s plan to vaccinate front-line workers with the AstraZeneca shot.

The changes go into effect immediately.

With files from CTV News Vancouver's Ian Holliday